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Kapitel 1 führt - unter Berücksichtigung gesamtgesellschaftlicher Tendenzen im Hinblick auf verschiedene Lebensformen - zunächst in das Thema ein. Auf Basis der Tatsache geringer Scheidungsraten von Managerehen werden unterschiedliche Annahmen formuliert, die für die Ehestabilität dieser Paare eine Rolle spielen könnten.
Im Weiteren werden hier wesentliche Fragestellungen zum Thema der vorliegenden Arbeit und deren Zielsetzung begründet. Kapitel 2 fasst den aktuellen Forschungsstand zusammen. Bisherige Untersuchungsergebnisse zum Themenfeld Manager und deren Ehen sowie auch der Ehestabilitätsforschung werden hier vorgestellt und auf ihre Relevanz hin befragt. Ziel ist es, bereits gewonnene Ergebnisse nach ihrer Bedeutung für diese Arbeit zu bewerten und entsprechende Fragestellungen daraus abzuleiten. Kapitel 3 setzt sich mit theoretischen Ansätzen zur Erklärung von Ehestabilität auseinander. Vor dem Hintergrund verschiedener Handlungsmodelle stellt sich die Frage, ob die Stabilität von Managerehen das Ergebnis von wertorientiertem, zweckorientiertem oder gar traditionalem Handeln ist. Insbesondere werden hier der kultursoziologische Ansatz von Schreiber und die Rational Choice Theorie von Esser als maßgebliche theoretische Grundlage für den Leitfaden und die Auswertung des empirischen Materials vorgestellt und erläutert. Im Anschluss daran erklärt Kapitel 4 die Voraussetzungen und den Ablauf der Erhebung der Daten und beschreibt die Paare des vorliegenden Samples. Als Methode der Befragung wurde das Leitfadeninterview gewählt, welches begründet und von seiner Konzeption wie auch seinen Inhalten her beschrieben wird. Die Erläuterung zur Durchführung der Interviews und zur Methode der Analyse der Gespräche bilden den Abschluss dieses Kapitels. Kapitel 5 führt sodann in das vorliegende empirische Material ein. Es dient der Beschreibung der interviewten Paare in der Darstellungsform von insgesamt zehn Paarportraits. Ziel hierbei ist zum einen, die Beziehungswelt der Paare abzubilden, zum anderen zu zeigen, dass es bei allen Befragten prägnant wiederkehrende Strukturelemente innerhalb der Beziehung gibt. Diese geben einen ersten Hinweis auf die besonderen Stabilitätsfaktoren von Managerehen. Das folgende Kapitel 6 fasst die Erfolgsfaktoren ehelicher Stabilität der befragten Paare zusammen. Es kann aufzeigen, wie die Faktoren Heiratsmotivation, Rollenverteilung, Paarinteraktion, Statussymbole, soziales Umfeld, Beziehungswünsche und -visionen von den Paaren beschrieben werden und welche Rolle sie im Hinblick auf die Ehestabilität der Paare spielen. Hier wird deutlich dass es bei den Aussagen der Befragten große Strukturähnlichkeiten gibt, die es erlauben von einem Sondertypus "stabile Ehe" zu sprechen. In einer zusammenfassenden Beschreibung wird herausgestellt, welche Merkmale diesen besonderen Typus kennzeichnen und was ihn letztendlich charakterisiert. Managerehepaare leben in einer erfolgreichen Lebensform zusammen. Sie stellen einen Sondertypus unter den bisher bekannten Lebensformen dar. Das Schlusskapitel 7 fasst die Ergebnisse dieser Arbeit zusammen und pointiert sie in der Konstruktion einer managerspezifischen Lebensform, für die der Name LTA (Living Together Apart)20 gewählt wurde.
Agricultural pesticides, especially insecticides, are an integral part of modern farming. However, these may often leave their target ecosystems and cause adverse effects in non- target, especially freshwater ecosystems, leading to their deterioration. In this thesis, the focus will be on Insect Growth Regulators (IGRs) that can in many ways cause disruption of the endocrine system of invertebrates. Freshwater invertebrates play important ecological, economic and medical roles, and disruption of their endocrine systems may be crucial, considering the important role hormones play in the developmental and reproductive processes in organisms. Although Endocrine Disruption Chemicals (EDCs) can affect moulting, behaviour, morphology, sexual maturity, time to first brood, egg development time, brood size (fecundity), and sex determination in invertebrates, there is currently no agreement upon how to characterize and assess endocrine disruption (ED). Current traditional ecotoxicity tests for Ecological Risk Assessment (ERA) show limitations on generating data at the population level that may be relevant for the assessment of EDCs, which effects may be sublethal, latent and persist for several generations of species (transgenerational).
It is therefore the primary objective of this thesis to use a test method to investigate adverse effects of EDCs on endpoints concerning development and reproduction in freshwater invertebrates. The full life-cycle test over two generations that includes all sensitive life stages of C. riparius (a sexual reproductive organism) allows an assessment of its reproduction and should be suitable for the investigation of long-term toxicity of EDCs in freshwater invertebrates. C. riparius is appropriate for this purpose because of its short life cycle that enables the assessment of functional endpoints of the organism over several generations. Moreover, the chironomid life cycle consists of a complete metamorphosis controlled by a well-known endocrine mechanism and the endocrine system of insects has been most investigated in great detail among invertebrates. Hence, the full life-cycle test with C. riparius provides an approach to assess functional endpoints (e.g. reproduction, sex ratio) that are population-relevant as a useful amendment to the ERA of EDCs. In the laboratory, C. riparius was exposed to environmentally-relevant concentrations of the selected IGRs in either spiked water or spiked sediment scenario over two subsequent generations.
The results reported in this thesis revealed significant effects of the IGRs on the development and the reproduction of C. riparius with the second (F1) generation showing greater sensitivity. These findings indicated for the first time the suitability of multigenerational testing for various groups of EDCs and strongly suggested considering the full life-cycle of C. riparius as an appropriate test method for a better assessment of EDCs in the freshwater environment. In conclusion, this thesis helps to detect additional information that can be extrapolated at population level and, thus, might contribute to better protection of freshwater ecosystems against the risks of Endocrine Disrupting Chemicals (EDCs.) It may furthermore contribute to changes in the ERA process that are necessary for a real implementation of the new European chemical legislation, REACH (Registration, Evaluation Authorization and Restriction of Chemicals). Finally, significant interactions between temperature, chemical exposure and generation were reported for the first time and, may help predict impacts that may occur in the future, in the field, under predicted climate change scenarios.
The conservation of groundwater ecosystems requires an assessment and evaluation scheme that shows the state of the ecosystem. Consequently, faunal and microbial criteria are required for groundwater monitoring, in addition to physico-chemical analyses. To proof the adequacy of the application of groundwater organisms for the biological assessment of groundwater quality, an extensive sampling collection of various groundwater systems was accomplished between 2002 and 2009 in Germany. Key aspects were the examination of the indicator potential of groundwater communities towards surface-groundwater interactions and anthropogenic impacts, as well as the analysis of stygofaunal distribution patterns, as a base and reference for a faunal assessment scheme of groundwater systems. The sampling design considered local, regional, and biogeographic conditions. To test the indicator potential of groundwater organisms on a local and regional scale, groundwater systems in Nordrhein-Westfalen (NRW) and Baden-Württemberg (BW) were examined. The faunal and microbial data from unconsolidated aquifers (Erftgebiet, NRW) show the sensitivity of groundwater organisms against land use effects, e.g. extensive agriculture. Data analyses revealed positive correlations of organic material (estimated amount of detritus, TOC) and nitrate with faunal abundance, species richness, diversity and the proportions of stygoxene species. Moreover, the bacterial abundance and diversity in the groundwater of the Erftgebiet was high compared to oligotrophic groundwater systems, indicating an effect of surface influence due to agricultural land use. The groundwater colonization in the Alb-Donau-Kreis (BW) was analyzed for regional effects (landscape, type of aquifer, hydrogeology) and local effects (comparing single wells). The results show that the fauna reflects the strength of the hydrological exchange on different spatial scales. Furthermore, the fauna reflects the interaction of regional and local conditions. Accordingly, the diversity and abundance of groundwater organisms was influenced by the high connectivity of the karst and unconsolidated alluvial aquifers, the type of land use, covering layers of soil, the age of groundwater, and the sampling depths. In general, faunal and microbial data of the Alb-Donau-Kreis are characteristic for oligotrophic, oligoalimonic groundwaters. The large scale analyses of stygofaunal distribution patterns revealed significant biogeographical differences of the communities. These community patterns of the groundwater fauna do not coincide with existing classification schemes defined for surface landscapes or freshwater systems. The largest differences between faunal surface and subsurface distribution patterns were found between the groundwater of northern and southern Germany and the foothills of the central mountain ranges - all of them regions shaped by the last ice ages.
In accordance with the faunal data assessed in groundwater, four different stygoregions were defined that are populated by distinct faunal assemblages. These are 1) the "Northern lowlands", 2) the "Central mountain ranges", 3) the "South-western mountain ranges", and 4) the "Southern mountain ranges and northern alps". The study corroborates that stygofaunal and microbial communities are an adequate tool for the qualitative assessment and monitoring of groundwater ecosystems. The best indicators to detect anthropogenic impacts on groundwater ecosystems are the faunal diversity, abundance, the proportions of stygobitic (obligate groundwater species) and stygoxene species (species not obligate for groundwater), and the bacterial abundance. The development of an ecologically based groundwater assessment and management, is crucial for the conservation of our groundwater ecosystems and thus, healthy drinking water. The defintion of "stygoregions" is an important base for the development of an assessment and reference scheme for groundwater ecosystems. The assessment of the ecological state of groundwater systems must be conducted on local scale, because the strength of the local hydrological influence determines the amount of food and oxygen as well as stygoxene animals within the aquifer, and thus shapes the local groundwater communities. Nevertheless, information of the biogeographic and regional conditions is needed as a reference for the type of species and abundances that potentially can occur in certain groundwater systems.
Worldwide one third to one half of the freshwater crayfish species are threatened with population decline or extinction. Besides habitat deterioration, pollution, and other man-made environmental changes, invasive species and pathogens are major threats to the survival of European crayfish species. Freshwater crayfish are the largest freshwater invertebrates and strongly influence the structure of food webs. The disappearance of crayfish from a water body may change the food web and could have dramatic consequences for an ecosystem.rnOne goal in modern species conservation strategies is the conservation of genetic diversity, since genetic diversity is an advantage for the long-term survival of a species. The main aim of my thesis was to reveal the genetic structure and to identify genetic hotspots of the endangered noble crayfish (Astacus astacus) throughout Europe (part 1 of my thesis). Since the most significant threat to biodiversity of European crayfish species is the crayfish plague pathogen Aphanomyces astaci I studied new aspects in the distribution of A. astaci (part two of my thesis). The results serve as a basis for future conservation programs for freshwater crayfish. In the first part of my thesis I conducted a phylogeographic analysis of noble crayfish using mitochondrial DNA and nuclear microsatellite data. With these methods I aimed to identify its genetic hotspots and to reconstruct the recolonization history of central Europe by this species. I detected high genetic diversities in southestern Europe indicating that noble crayfish outlasted the cold climate phases during the Pleistocene in this region (Appendix 1). Because of the high genetic diversity found there, southeastern Europe is of particular importance for the conservation of noble crayfish. The mitochondrial DNA analysis points to a bifurcated colonization process from the eastern Black Sea basin to a) the North Sea and to b) the Baltic Sea basin (Appendix 2). A second independent refugium that was localized on the Western Balkans did not contribute to the colonization of central Europe. Furthermore, I found that the natural genetic structure is dissolved, probably due to the high human impact on the distribution of noble crayfish (e.g. artificial translocation). In the second part of this thesis using real-time PCR I identified calico crayfish (Orconectes immunis) as the fourth North American crayfish species to be carrier of the agent of the crayfish plague (Appendix 3). Furthermore I detected the crayfish plague pathogen in American spiny-cheek crayfish (Orconectes limosus) and native narrow-clawed crayfish (Astacus leptodactylus) in the lower Danube in Romania (Appendix 4). The distribution of infected spiny-cheek crayfish poses a threat to the native biodiversity in southeastern Europe and shows the high invasion potential of this crayfish species. Moreover, I found that even the native narrow-clawed crayfish in the Danube Delta, about 970 km downstream of the current invasion front of American crayfish, is a carrier of A. astaci (Appendix 5). This finding is of high importance, as the native species do not seem to suffer from the infection. In Appendix 6 I elucidate demonstrate that the absence of the crayfish plague agent is the most likely explanation for the coexistence of populations of European and American crayfish in central Europe. In my thesis I show that the common assumption that all North American crayfish are carrier of A. astaci and that all native crayfish species die when infected with A. astaci does not hold true. The studies presented in my thesis reveal new aspects that are crucial for native crayfish conservation: 1) The genetic diversity of noble crayfish is highest in southeastern Europe where noble crayfish outlasted the last glacial maximum in at least two different refugia. 2) Not all American crayfish populations are carrier of A. astaci and 3) not all Europen crayish populations die shortly after being infected with the crayfish plague pathogen.rnTo conserve native crayfish species and their (genetic) diversity in the long term, further introductions of American crayfish into European waters must be avoided. However, the introduction will only decrease if the commercial trade with non-indigenous crayfish species is prohibited.
This dissertation investigates the usage of theorem provers in automated question answering (QA). QA systems attempt to compute correct answers for questions phrased in a natural language. Commonly they utilize a multitude of methods from computational linguistics and knowledge representation to process the questions and to obtain the answers from extensive knowledge bases. These methods are often syntax-based, and they cannot derive implicit knowledge. Automated theorem provers (ATP) on the other hand can compute logical derivations with millions of inference steps. By integrating a prover into a QA system this reasoning strength could be harnessed to deduce new knowledge from the facts in the knowledge base and thereby improve the QA capabilities. This involves challenges in that the contrary approaches of QA and automated reasoning must be combined: QA methods normally aim for speed and robustness to obtain useful results even from incomplete of faulty data, whereas ATP systems employ logical calculi to derive unambiguous and rigorous proofs. The latter approach is difficult to reconcile with the quantity and the quality of the knowledge bases in QA. The dissertation describes modifications to ATP systems in order to overcome these obstacles. The central example is the theorem prover E-KRHyper which was developed by the author at the Universität Koblenz-Landau. As part of the research work for this dissertation E-KRHyper was embedded into a framework of components for natural language processing, information retrieval and knowledge representation, together forming the QA system LogAnswer.
Also presented are additional extensions to the prover implementation and the underlying calculi which go beyond enhancing the reasoning strength of QA systems by giving access to external knowledge sources like web services. These allow the prover to fill gaps in the knowledge during the derivation, or to use external ontologies in other ways, for example for abductive reasoning. While the modifications and extensions detailed in the dissertation are a direct result of adapting an ATP system to QA, some of them can be useful for automated reasoning in general. Evaluation results from experiments and competition participations demonstrate the effectiveness of the methods under discussion.
Die Dissertation "Schreibprozesse in der Wikipedia" untersucht auf Basis einer linguistischen Textanalyse individuelle und gemeinschaftliche Schreibhandlungen in der Wikipedia. An Beispiel ausgewählter Artikel werden Artikelinitiationen, Handlungsmuster beim Er- und Überarbeiten der Texte, Prozesse des Planens, Gliederns und Bewertens sowie Kontroversen, Edit Wars und Vandalismus als grundlegende Aspekte des Schreibens in gemeinschaftlichen Online-Kontexten betrachtet. Dabei erscheinen vor allem Kontroversen als ein in der Schreibforschung bisher vernachlässigter Einflussfaktor, der nicht nur Auswirkungen auf die Schreibprozesse in der Wikipedia, sondern auch auf die gesamte Abbildung, Genese und vor allem Aushandlung von Wissen hat.
Früher wurden in Museen den Besuchern meist gesicherte Wissensbestände präsentiert. Heute ist das vielfach anders: Nicht nur fraglos geltendes Wissen, sondern auch der Prozess dorthin wird aufgezeigt. Die dargebotene Information ist teilweise nicht mehr konsistent und widerspruchsfrei sondern konfligierend. Wie aber reagieren die Besucher auf konfligierende Information? Wie unterstützen ihre persönlichen Vorrausetzungen eine differenziertere Betrachtung? Wie können Museen " obwohl ihre Information doch freiwillig, selbstbestimmt, ohne Zwang und Pression rezipiert wird - die Informationsverarbeitung ihrer Besucher durch eine bestimmte räumliche Informationsanordnung beeinflussen? Diese Fragen wurden mittels vier Feldstudien vor Ort untersucht:
Studie 1 charakterisiert Museumsbesucher durch Persönlichkeitsprofile, die aus den für die Verarbeitung konfligierender Information als relevant betrachteten Personenmerkmalen (epistemologischen Überzeugungen, Ambiguitätstoleranz, Selbstwirksamkeitsannahmen) erstellt sind.
Studie 2 untersucht den Einfluss dieser Personenmerkmale und des situationalen Interesses auf die Tendenz zur Konfliktverarbeitung, ohne Fähigkeiten und Fassungskraft des Besuchers zu berücksichtigen.
Studie 3 überprüft die Effekte von situationalem Interesse, epistemologischen Überzeugungen, Ambiguitätstoleranz und Selbstwirksamkeitsannahmen auf die Konfliktverarbeitungsleistung.
In Studie 4 wird schließlich die Wirkung räumlich naher Informationspräsentation untersucht.
Museumsbesucher können durch die Persönlichkeitsprofile "selbstzweifelnd skeptisch", "selbstbewusst vertrauensvoll" und "stabilitätsgläubig" charakterisiert werden. Eine überwältigende Mehrheit zeigt die Bereitschaft, Konflikte wahrzunehmen und ein großer Teil ist darüber hinaus bereit, konfligierende Informationen auf tieferer Ebene zu verarbeiten. Eine räumlich nahe (thematisch kontinuierliche) Präsentation unterstützt die Tendenz, tief zu verarbeiten. Etwa drei Viertel der Besucher konnten erkennen, wann konfligierende Information logisch widersprüchlich ist und konnten überzufällig gut bei konsistenter und konfligierender Information Kohärenz bilden. Positive Selbstwirksamkeitsannahmen unterstützen vermittelt über hohes situationales Interesse die Tendenz, Information tiefer zu verarbeiten und steigern die Fähigkeit, Kohärenz zu bilden. Reifere epistemologische Überzeugungen der Dimension "Sicherheit" und "Veränderlichkeit" fördern Kohärenzbildung.
Galerucinae, Latreille 1802 is the second largest subgroup of chrysomelidae. 1837 Chervrolat described the taxon Ootheca, which has originally only one listed species. Nearly 200 years all galerucinae with a "compact" bodyshape, a broad pronotum, a convex dorsum , short antennae and short legs were assigned to Ootheca. When I started a revision of Ootheca, this taxon included 38 species. Comparing morphological characters of the exoskeleton combined with the depiction/description of characteristic structures of the male genitalia allowed a detailed description of the genus Ootheca and its species. After the revision 9 valid species remained in Ootheca, 4 are described to be new, 13 species were transferred to other valid described genera and 10 species remained, because of a lack of unambiguous assignment. The examination of the median lobe additionally enables me to describe three sister taxa: Oothecoides (6 species), Ootibia (5 species ) und Oosagitta (6 species).
English prepositions take only a small proportion of the language but play a substantial role. Although prepositions are of course also frequently used in English textbooks for secondary school, students fail to incidentally acquire them and often show low achievements in using prepositions correctly. The strategy commonly employed by language instructors is teaching the multiple senses of prepositions by rote which fails to help the students to draw links between the different meanings in usage. New findings in Cognitive Linguistics (CL) suggest a different approach to teaching prepositions and thus might have a strong impact on the methodologies of foreign language teaching and learning on the aspects of meaningful learning. Based on the Theory of Domains (Langacker, 1987), the notions of image schemas (Johnson, 1987) as well as the Conceptual Metaphor Theory (Lakoff & Johnson, 1980), the present study developed a CL-inspired approach to teaching prepositions, which was compared to the traditional teaching method by an empirical study conducted in a German school setting. Referring to the participants from the higher track and the medium track, who are at different proficiency levels, the results indicate that the CL-inspired teaching approach improved students" performance significantly more than the traditional approach in all the cases for the higher track and in some cases for the medium track. Thus, these findings open up a new perspective of the CL-inspired meaningful learning approach on language teaching. In addition, the CL-inspired approach demonstrates the unification of the integrated model of text and picture comprehension (the ITPC model) in integrating the new knowledge with related prior knowledge in the cognitive structure. According to the learning procedure of the ITPC model, the image schema as visual image is first perceived through the sensory register, then is processed in the working memory by conceptual metaphor, and finally it is integrated with cognitive schemata in the long term memory. Moreover, deep-seated factors, such as transfer of mother tongue, the difficulty of teaching materials, and the influence of prior knowledge, have strong effects on the acquisition of English prepositions.
Studies on the toxicity of chemical mixtures find that components at levels below no-observed-effect concentrations (NOECs) may cause toxicity resulting from the combined effects of mixed chemicals. However, chemical risk assessment frequently focuses on individual chemical substances, although most living organisms are substantially exposed to chemical mixtures rather than single substances. The concepts of additive toxicity, concentration addition (CA), and independent action (IA) models are often applied to predict the mixture toxicity of similarly and dissimilarly acting chemicals, respectively. However, living organisms and the environment may be exposed to both types of chemicals at the same time and location. In addition, experimental acquisition of toxicity data for every conceivable mixture is unfeasible since the number of chemical combinations is extremely large. Therefore, an integrated model to predict mixture toxicity on the basis of single mixture components having various modes of toxic action (MoAs) needs to be developed. The objectives of the present study were to analyze the challenges in predicting mixture toxicity in the environment, and to develop integrated models that overcome the limitations of the existing prediction models for estimating the toxicity of non-interactive mixtures through computational models. For these goals, four sub-topics were generated in this study. Firstly, applicable domains and limitations of existing integrated models were analyzed and grouped into three kinds of categories in this study. There are current approaches used to assess mixture toxicity; however, there is a need for a new research concept to overcome challenges associated with such approaches, which recent studies have addressed. These approaches are discussed with particular emphasis on those studies involved in computational approaches to predict the toxicity of chemical mixtures based on the toxicological data of individual chemicals. Secondly, through a case study and a computational simulation, it was found that the Key Critical Component (KCC) and Composite Reciprocal (CR) methods (as described in the European Union (EU) draft technical guidance notes for calculating the Predicted No Effect Concentration (PNEC) and Derived No Effect Level (DNEL) of mixtures) could derive significantly different results. As the third and fourth sub-topics of this study, the following two integrated addition models were developed and successfully applied to overcome the inherent limitations of the CA and IA models, which could be theoretically used for either similarly or dissimilarly acting chemicals: i) a Partial Least Squares-Based Integrated Addition Model (PLS-IAM), and, ii) a Quantitative Structure-Activity Relationship-Based Two-Stage Prediction (QSAR-TSP) model. In this study, it was shown that the PLS-IAM might be useful to estimate mixture toxicity when the toxicity data of similar mixtures having the same compositions were available. In the case of the QSAR-TSP model, it showed the potential to overcome the critical limitation of the conventional TSP model, which requires knowledge of the MoAs for all chemicals. Therefore, this study presented good potential for the advanced integrated models (e.g., PLS-IAM and QSAR-TSP), while considering various non-interactive constituents that have different MoAs in order to increase the reliance of conventional models and simplify the procedure for risk assessment of mixtures.